High speed bearings, for example those used to support a 4" shaft or spindle rotating at 2600 r.p.m. or so, generate considerable heat. The outer bearing rings or races have a tendency to slip during operation because of differential expansion, due to the fact that the housing is cooled by the ambiant air and hence is at a much lower temperature than the outer rings. (The inner bearing rings or races, being at substantially the same temperature as the shaft, have no tendency to slip when merely shrunk on the shaft.) Accordingly, it is often necessary to key the outer bearing rings to the housing.
It is also known that excessive lubricant in bearings of a high speed application can be detrimental in that such excessive lubricant tends to churn and develop heat. Therefore, it is an object of this invention to prevent excessive accumulation of lubricant by providing means for a regulated flow of lubricant and to incorporate such means in the arrangement for mounting and keying the spindle bearings.
Other objects and features of the invention will become apparent as the following description proceeds, especially when considered with the accompanying drawings.